Suspension means



Aug. 26, 1969 A. F. HOBBS 3,463,468

' SUSPENSION MEANS" Filed on. 18. 1967 a sheets-sheet 1 Aug. 26, 1969Filed Oct. 18. 1967 Mid A. F. HOBBS SUSPENSION MEANS S Sheets-Sheet 2Aug. 26, 1969 Filed on. 18. 19s? A. F. HOBBS SUSPENSION MEANS I5Sheets-Sheet 5 United States Patent 3,463,468 SUSPENSION MEANS ArthurFrederick Hobbs, London, England, asslgnor to Humphrey & GlasgowLimited, London, England, a British company Filed Oct. 18, 1967, Ser.No. 676,306 Claims priority, application Great Britain, Oct. 20, 1966,47,062/66 Int. Cl. F27b 7/00; F23m 7/00; F16c 1/10 US. Cl. 263-33 8Claims ABSTRACT OF THE DISCLOSURE Suspension means for a non-rotatingend cover for sealing a rotary kiln comprising a pair of levers, orlever systems, two frames for mounting the levers or systemsrespectively, means to mount each frame for horizontal movement alongparallel paths whereby each lever or system may be moved individuallywith its respective frame, means for pivotally attaching an end cover atspaced locations on the cover to one end of each of the levers orsystems respectively, and two counterbalancing means attached to theother end of each lever or system, the arrangement of the levers orsystems being such that there is a mechanic-a1 advantage in favour ofthe counterweights.

This invention relates to the construction of suspension means forrotary kilns and similar rotary devices.

More particularly it is concerned with suspension means for supportingthe stationary end cover or end box which seals one end of such a kilnor device and may be provided with means for feeding materials into thekiln or for removal of a product or products from the kiln, for instanceevolved gases.

The effective seal between such an end cover and the kiln generallytakes the form of a 'spigoted joint, one section of which is formed onthe end face of the kiln and the other on the end cover, which isnecessarily of massive construction.

Together with the necessary gas conduit means, or the like, an end covermay have considerable weight, for instance from four to eight tons.

So that the seal may be elfective it is necessary that the height of theend cover may be adjustable within fine limits, and this setting bemaintained during operation, while for other purposes, such as assemblyand maintenance, larger controlled movement both vertically andlongitudinally must also be possible. An automatically maintainedpressure between the sealing surfaces of the kiln and the end cover isalso desirable. Further, where the kiln is arranged at an angle to thehorizontal an end cover may be held suspended at an angle to thevertical correspondingly.

The invention provides suspension means for a nonrotating end cover forsealing a rotary kiln comprising a pair of levers, or lever systems, twoframes for mounting the levers or systems respectively, means to mounteach frame for horizontal movement along parallel paths whereby eachlever or system may be moved individually with its respective frame,means for pivotally attaching an end cover at spaced locations on thecover to one end of each of the levers or systems respectively, and twocounterbal-ancing means attached to the other end of each lever orsystem, the arrangement of the levers or systems being such that thereis a mechanical advantage in favour of the counterweights.

Preferably compound lever systems are employed.

Preferably also there are on the frames support means below thecounterweights so that in the event of failure 3,463,468 Patented Aug.26, 1969 of the means suspending the counterweights the distance theweights may fall is limited.

There may he means on each frame to lock or limit movement of thelevers.

There may be chains or the like to connect the end cover to the levers,the length of which chains may be adjustable.

In one embodiment a damping device is provided on at least one of thesystems to damp any sudden downward force applied to the system (e.g.when the kiln is rotated in a direction to produce such a downwardfrictional force on the end cover).

Preferably the mounting means for the frames comprise pulleys movablealong horizontal parallel rails, and there may be means to lock eachframe relative to its respective rail.

A specific example of suspension means for an end cover of a rotary kilnwill now be described with reference to the accompanying drawings in.which:

FIGURE 1 is a side view of the suspension means,

FIGURE 2 is an end view of the suspension means,

FIGURE 3 is an enlarged scrap view of the locking means for the levers,and

FIGURE 4 shows an alternative suspension for the counterweights.

In these figures, 1 represents a rotary kiln and 2 an end coversuspended at 2411 and 24b by chains 4a and 4b from compound leversystems 3a, 13a, 23a and 3b, 13b, 23b respectively. The levers arepivotally mounted at 5a, 5b and 6a, 6b respectively between plate likeframe members 7a, 17a and 7b, 17b.

The chains 4a and 4b are provided with means 8a and 8b for adjustingtheir length and thus the height of the end cover 2 and its orientationabout its centre.

The two sets of frame members carry paired rollers 10a, 11a and 10b, 11bwhich run upon rails 12a and 12b respectively, these rails beingsubstantially horizontal and parallel.

Each lever assembly may be locked in position along its rail by ananchoring device, for instance 14a attached to the plate-like member 7a.

From the free ends of the levers counterweights 9a and 9b are suspendedand their weight is adjustable by addition or removal of supplementaryweights. So that the fall of a counterweight should be limited in theevent of failure of its supporting chain each hangs freely within aframework (19a and 1912 respectively) which in turn is securelysupported from the plates 7a, 1701 and 7b, 17b respectively of thecorresponding lever assembly.

An alternative method of suspending the counterweights is illustrated inFIGURE 4. In this embodiment the flexible connection 4a of FIGURES 1 and2 between the lever 311 at 33a and one side of the end cover 2 at 2411is replaced by two chains 44a linked by a yoke 39a from which theconnection extends downwards as a bar 45a with means 8a for shorteningor lengthening the extension of the bar from the yoke. The base 14a isattached to the end cover at 2412.

The counterweight 9a is hung by the chain 29a from the free end of thelever 23a, the point of its suspension (40a in FIGURE 1) from that leverbeing such that it is nearly vertically superimposed above 33a, thepoint of suspension of the main load (the end cover) from lever 3a.

The chains 44:: pass through the counterweight 9a, which is suspendedabove the yoke 39a, and in the event of failure of the chain 29:: thecounterweight can fall only as far as the yoke.

For additional safety an enclosure 19a (shown in chained lines in FIGURE4) may be built upon the yoke 39a.

When necessary, for instance if the end cover 2 is to be removed fromcontact with the kiln 1, as for maintenance purposes, movement of thelever systems may be prevented entirely by setting an arresting means 15to lock the free ends 27 of the levers (see FIGURE 3). When theanchoring means 141: is freed longitudinal movement along the rails ofthe while suspension system and the end cover 2 becomes possible withoutchange in the vertical position of the cover and with complete safety.

For normal operation of the kiln, and once counterbalance of the endcover has been adjusted, the knifeedged ends 27 of the levers arereleased from the notched lever 15 and the levers are thus allowedfreedom of movement. The movement can be inspected visually at alltimes. During fine adjustment of the counterbalance the notched levers15 may be set as in FIGURE 3, to permit only limited movement of theends 27 of the levers.

It is apparent that the end cover 2. may be arranged to hang with itsbearing face at a desired angle to the vertical by choice of thepositions 24a and 24b on its periphery. These may be adjustable by meansnot shown in the figures.

A hydraulic damping device 20, coupled between the points 21 on theplate 70 and 22 on the lower lever 3a is arranged to restrict suddendownward movement of the lever 3a about the pivot a. Thus when the kilnis started from rest the additional frictional forces tending to rotatethe end cover will not cause over-travel of spring-loaded means 30coupled between 31 on the end cover and 32 on the kiln for the purposeof counteracting normal operational friction of the seal.

From the foregoing description and the accompanying figures it may beseen that a suspension means according to the invention has bigadvantages over conventional means comprising multiple pulleys andcounterweights.

For instance, the invention enables the position of the end cover to beadjusted and maintained within fine limits, and for assembly,maintenance and repair work to be carried out without substantialalteration of adjustments previously made.

The invention also has advantages from the aspect of safety.

I claim:

1. Suspension means for a non-rotating end cover for sealing a rotarykiln comprising a pair of compound lever systems, two frames formounting the lever systems respectively, means to mount each frame forhorizontal movement along parallel paths whereby each lever system maybe moved individually with its respective frame, means for pivotallyattaching an end cover at spaced locations on the cover to one end ofeach of the lever systems respectively, and two counterbalancing meansattached to the other end of each lever system, the arrangement of thelever systems being such that there is a mechanical advantage in favourof the counterweights.

2. Suspension means as claimed in claim 1 in which there is provided oneach frame below its respective counterbalance means support means tolimit the distance the counterbalance means may fall if thecounterbalance means becomes detached from the system.

3. Suspension means as claimed in claim 1 in which there is means oneach frame to lock or limit movement of the levers.

4. Suspension means as claimed in claim 1 in which there are flexibletension members connecting the end cover to the lever system.

5. Suspension means as claimed in claim 3 in which the lengths of thetension members are adjustable.

6. Suspension means as claimed in claim 1 in which a damping device isprovided on at least one of the systems to damp any sudden downwardforce applied to the system.

7. Suspension means as claimed in claim 1 in which the mounting meansfor the frames comprise rollers movable along horizontal parallel rails.

8. Suspension means as claimed in claim 7 in which there is means tolock each frame relative to its respective rail.

References Cited UNITED STATES PATENTS 3,019,835 2/1962 Maurand 263-33JOHN J. CAMBY, Primary Examiner US. Cl. X.R. 74-501; ll0-173

